do you have a wind cover? i recently switched from three kings to cocos too, at first i got mixed results. Now, I let them light for about 7 or 8 minutes (flipping them half way through) then take them off the stove plop them on opposite side of the bowl, and place a wind cover overr the bowl. after about a minute and a half i would have fatty clouds. i smoke AF and potion tobacco. i usually leave it on for a few minutes to "bake" the bowl a little and then remove it for the rest of the session. But im using a standard mya bowl. with a phunnel i use three cocos... and adjust the heat from there. im assuming you can use three cocos with a vortex bowl too.

as for water level? i fill the base to about an inch over the bottem of the down stem.